Conveyor chains and belts for use in material handling conveyors are commonly constructed from injection molded chain links assembled in side-by-side relation and joined together in rows by chain pins. Such chain links can be assembled to form chains of various widths depending on the number of chain links positioned together in side-by-side relation. Such chains and belts are constructed of molded chain links of at least two different widths to permit the chain links to be brick-laid. Bricklaying of the chain links results in increased strength of the chain in tension as well as increased transverse rigidity.
Such molded plastic conveyor chains are also used in conveyors originally designed to employ woven wire mesh conveyor belting. Such woven wire mesh belting, although limited in many respects, was commonly produced as a laced or woven material and could be conveniently produced or manufactured in any selected width. Because the woven wire mesh belting was available in any required width, conveyor manufacturers designed conveyor systems of varying widths and did not limit the conveyor designs to selected standard widths.
Plastic modular conveyor chains have replaced woven wire mesh conveyor belts because the plastic modular chains are light weight, corrosion resistant, easily cleaned and provide low friction properties without the use of lubricants. However, such modular conveyor chains are commonly molded in only specific sizes, such as modules which are 3-inches and 6-inches wide. In many applications for modular plastic chains such as in existing conveyor frames, the chains made of such molded plastic links can be made to accommodate the conveyor frame width only by cutting some or all of the molded chain links to form the required chain width. Although cutting of the modules to the required width produces a chain which will accommodate the conveyor frame, cutting of the chain module requires substantial time and labor in manufacture and assembly of the chain. Additionally, cutting of the modules results in waste of material. For example, if a 12-inch wide chain link is cut in half, this cutting process does not produce two modules each 6 inches in width. The cutting operation will produce one 6-inch module and a second module which is slightly less than 6 inches in width, that dimension being equal to the width of the saw blade or other cutting device. While it is possible to grind up the resulting waste plastic material of the shorter wasted portion of the chain link such that material can again be molded to form other modules, additional molding operations are expensive and time consuming.
Additionally, most chain modules are molded from materials such as acetal, polypropylene, polyester or polyethylene, and these materials burr significantly when machined or cut. These burrs must be removed to provide a tight fitting conveyor assembly which is flat and easy to clean. Removal of burrs is labor intensive and further adds to the expense of producing chain having a width which is other than a standard width.